500 Chapter 2.12 Design and Development of Standards (HL7 V3) Based Enterprise Architecture for Public Health Programs Integration at the County of Los Angeles Copyright © 2009, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited. Abdul-Malik Shakir CAL2CAL Corporation, USA David Cardenas L.A. County Department of Public Health, USA Gora Datta CAL2CAL Corporation, USA Debashish Mittra CAL2CAL Corporation, USA Arindam Basu CAL2CAL Corporation, USA Rini Verma CAL2CAL Corporation, USA AbstrAct Public Health (PH) applications in County of Los Angeles (LAC), Department of PH have been developed to meet individual PH program’s goals. This resulted in lack of county-wide PH data integration, effciency, and usefulness. LAC encouraged the development of web-based appli- cations utilizing standards-based PH Information Network interoperable service-oriented architec- ture (SOA). The goal was to stop the evolution of fragmented health data systems which place limitations on the PH mission of safeguarding and improving the health of the community as well as responding to large-scale threats to PH. PH Nursing case management is one example of LAC’s initiative for promotion of web-based tools which will be utilized within this SOA. This PH architecture is capable of supporting electronic data exchange from PH partners using a HL7 integration hub. It promotes the development of management tools and applications to assist PH response and recovery activities while providing resources to support departmental integration.